I'm curious to see how we gain new ATB abilities and how/if they're customizable. Skill trees? Unlocked through story progression? Associated with weapons and equipment?
I'd personally like something along the lines of abilities are unlocked through story progression and each skill has its own tree. The skill trees for each ability would allow you to tweak the abilities to better fit a certain play style. The skill tree bonuses could have things like
Reduced ATB cost - requires 1 bar of ATB to use but doesn't consume the whole bar.
Increase to burst gauge charge rate
Increase to stagger percentage - starts at 160% and each use of ability could raise by X%
Increased damage by X% to staggered enemy
Increase to limit gauge by X% when using ability
Maybe certain kinds of character buffs
Increased ATB charge rate for X seconds after using ability
Increased magic damge for X seconds after using ability
Increased physical damge for X seconds after using ability
Reduced magic damage taken for X seconds after using ability
Reduced physical damage taken for X seconds after using ability
Increased attack speed for X seconds after using ability
Increased move speed for X seconds after using ability
Certain ability specific things as well
Increased AoE range
Increased armor penetration
Increased range
Increased healing
I know certain abilities already have inherent bonuses to them. Example being Barrets Focused Shot is described as follows: A charged shot that expends all of Barret’s ATB gauge. Similar to Cloud’s focused thrust ability, the move fills up a good amount of the target’s burst meter. These skill trees would allow even more depth and customization to characters.
I guess from there it's either you can max out every skill as you progress or you're limited to a certain number of points you can use and have to choose which ones you favor. We'll call them skill points or SP. That could be for each skill or the entire tree as a whole. I prefer the latter option. At the end of the game you have something like 150 possible SP options but you only have 100 SP to spend. That adds a strategic element in character progression and setting up different play styles for each character rather than you just get to spend 150/150. Each skill in the tree for each ability could have levels to it. For example Clouds Braver could look something like this.
Braver - Strong single enemy attack with a small AoE range
1 - Increase armor penetration of Braver by 1/3/5/7/10%
2 - Braver now increases staggered damage percentage by 2/5/10% for duration of stagger
3 - 5/10/20% of ATB charge will be refunded after using Braver
4 - ATB charge rate increased by 5/10/15/20% for 5/5/10/15 seconds after using Braver
5 - Braver does 3/5/8/10/15% more damage to staggered foes
There's 5 different choices with a combined number of 20 SP required to unlock them all. Say you only have 10 points to use at the time. You could turn Braver into a strong attack you use on already staggered foes by putting 1=5 points, 5=5 points. Maybe you want to use it to better build your ATB and use a different ability. You could do a 4=4 points, 3=3 points, and save the extra 3 points for another ability. Maybe you want to use Braver to increase the stagger % and your other abilities or characters can better capitalize with their skills. You could do 2=3 points, 3=3 points, 4=4 points.
Using my last Braver choice this allows you to use Cloud as more of a support character. Barret could use his SP to turn into a burst meter charging machine. His SP are spent on allowing him to use Focused Shot more often and increasing the burst charge rate. Barrets keeping his distance and firing away raising that burst meter. Once the enemies burst meters filled and the targets staggered Cloud comes in and increases the staggered damage %. He's able to use Braver often and before stagger is over the targets stagger bonus is capped at 250% (just assuming it's capped somewhere). HERE COMES TIFA!!! Tifa uses her SP to increase damage against staggered foes. She comes in and pumps out massive damage before stagger ends.
That example only takes into effect burst charge rate, stagger damage bonus %, and damage to staggered foe % increase. As we know elemental, magic, items, summons, materia, basic attacks, ground vs air based enemies, dodging and blocking are all parts of the battle mechanics as well. Characters triangle skills, square attacks, summons, limit breaks, items, dodge, and block could possibly have their own SP trees as well. Could opt for a higher attack speed, dodge distance, increased block damage, attack power, magic power, etc. for certain characters compared to others. I've mostly given offensive examples. Defensive things would be just as important.
They've already done a great job on making each character unique. It looks like every character will feel significantly different from one another. I'm really happy about that. Maybe characters and their abilities are innately built better for certain battle mechanics. I'm sure that's the case to some extent but i'd still enjoy a way to tweak things and allow even deeper depth to character customization. I love the skill tree idea personally. That on top of the materia system... Ooooh boy that'd allow for some really in depth customization.